UTHSC Fall 2022 D2 Par 1 Pathology
Pathology
the study of disease
Pathology consists of what four aspects?
- Etiology
- Pathogenesis
- Molecular and morphologic changes
- Clinical manifestations
Etiology
The cause of the disease or condition
- Genetic
- Acquired
- Ultimately most are multifactorial
Pathogenesis
The sequence of events from the etiology to clinical expression or manifestations
Molecular and morphologic changes
Alterations that may be characteristic or diagnostic. Pathology is becoming increasingly
involved in the use of molecular or immunologic techniques
Clinical manifestations
The end results of the disease process
what responses will a cell have to severe stress?
adapt, undergo injury or die
Cellular Adaptations
Reversible and structural responses to stresses
- Hypertrophy
- Hyperplasia
- Atrophy
- Metaplasia
cellular injury
May be reversible or irreversible
cellular death
- Necrosis
- Apoptosis
Hypertrophy
Increase in cell size, resulting in increase in the size of the organ
Hypertrophy is caused by
increased functional demand or hormonal stimulation
Hyperplasia
Increase in the number of cells and increased tissue mass
T/F hyperplasia may be physiologic but not pathologic
False, it can be both
what two kinds of things can physiologic hyperplasia fall under?
- Hormonal
- Compensatory
Pathologic hyperplasia is most often caused by
excess hormones or growth factors
,what is pathologic hyperplasia is sometimes associated with what?
increased risk of malignancy
Atrophy
the reduction in size of an organ or tissue
what causes atrophy?
- Decreased workload
- Loss of innervation
- Diminished blood supply
- Inadequate nutrition
- Loss of endocrine stimulation
Metaplasia
when one different cell type is replaced by another cell type
- Squamous metaplasia
- Intestinal metaplasia
Injury to somatic cells may arise from a number of processes such as
- Oxygen deprivation
- Physical agents (trauma, burns, etc.)
- Chemical agents/drugs
- Infectious agents
- Immunologic reactions
- Genetic derangements
- Nutritional imbalances
Stresses or noxious stimuli first effect the cell at what level?
molecular or biochemical
what do molecular and biochemical changes in cells eventually lead to?
morphologic changes
Morphologic changes are associated with what effects in cell injury?
decreased ATP synthesis, loss of membrane integrity, defective protein synthesis,
cytoskeletal damage and DNA damage
Early cell injury morphological changes are (irreversible/reversible)
reversible
Persistent injury results in cell
death by necrosis or apoptosis
Reversible cell injury is recognized microscopically as
cellular swelling or fatty change
what cells typically show fatty change?
cells involved in and dependent upon fat metabolism
What are some ultrastructural changes of reversible cell injury
- Plasma membrane alterations, such as blebbing, blunting and loss if microvilli
- Mitochondrial changes including swelling
- Dilation of the ER along with detachment of the polysomes
- Nuclear alterations, with disaggregation of granular and fibrillar elements
The cellular response to stresses depends upon what three things?
the nature of the injury, its duration and severity.
Consequences of cell injury depend upon
the type of cell, its state and adaptability
, what are some mechanisms of cell injury?
- Depletion of ATP
- Mitochondrial damage
- Influx of calcium and loss of homeostasis
- Accumulation of oxygen
-derived free radicals
- Defects in membrane permeability
- Damage to DNA and proteins
Depletion of ATP occurs secondary to
- Reduced oxygen or nutrient supply
- Mitochondrial damage
- Toxins
why will mitochondrial damage lead to necrosis or apoptosis?
by depleting ATP or the release of apoptotic activating proteins
Influx of calcium activates what enzymes?
enzymes with the potential for membrane or nuclear damage
Free radicals (superoxide, hydrogen peroxide and hydroxyl radicals)
have a single unpaired electron
free radical damage occurs
secondary to lipid peroxidation in membranes, oxidative modifications of proteins or
DNA damage
Antioxidants
capable of inactivating free radicals and preventing cellular injury
Defects in membrane permeability lead to
membrane damage which is common to most forms of cell injury
what are the most common types of cell injury?
hypoxia & ischemia
Hypoxia
Reduced oxygen. Energy production able to continue by anaerobic means
Ischemia
Reduced blood flow
what provides an indication of cell death clinically?
the leakage of intracellular enzymes and other proteins into the blood
what are the effects of cellular ischemia?
- Loss of oxidative phosphorylation and decreased ATP
- Cell and mitochondrial swelling
- Surface "blebs"
- ER dilation
- Decreased protein synthesis
ischemia is (irreversible/reversible)
irreversible
hypoxia is (irreversible/reversible)
reversible
what are the Cellular changes of necrosis?
- Cell Swelling
- Cytoplasm becomes glassy, homogenous and pink and may have vacuoles
Pathology
the study of disease
Pathology consists of what four aspects?
- Etiology
- Pathogenesis
- Molecular and morphologic changes
- Clinical manifestations
Etiology
The cause of the disease or condition
- Genetic
- Acquired
- Ultimately most are multifactorial
Pathogenesis
The sequence of events from the etiology to clinical expression or manifestations
Molecular and morphologic changes
Alterations that may be characteristic or diagnostic. Pathology is becoming increasingly
involved in the use of molecular or immunologic techniques
Clinical manifestations
The end results of the disease process
what responses will a cell have to severe stress?
adapt, undergo injury or die
Cellular Adaptations
Reversible and structural responses to stresses
- Hypertrophy
- Hyperplasia
- Atrophy
- Metaplasia
cellular injury
May be reversible or irreversible
cellular death
- Necrosis
- Apoptosis
Hypertrophy
Increase in cell size, resulting in increase in the size of the organ
Hypertrophy is caused by
increased functional demand or hormonal stimulation
Hyperplasia
Increase in the number of cells and increased tissue mass
T/F hyperplasia may be physiologic but not pathologic
False, it can be both
what two kinds of things can physiologic hyperplasia fall under?
- Hormonal
- Compensatory
Pathologic hyperplasia is most often caused by
excess hormones or growth factors
,what is pathologic hyperplasia is sometimes associated with what?
increased risk of malignancy
Atrophy
the reduction in size of an organ or tissue
what causes atrophy?
- Decreased workload
- Loss of innervation
- Diminished blood supply
- Inadequate nutrition
- Loss of endocrine stimulation
Metaplasia
when one different cell type is replaced by another cell type
- Squamous metaplasia
- Intestinal metaplasia
Injury to somatic cells may arise from a number of processes such as
- Oxygen deprivation
- Physical agents (trauma, burns, etc.)
- Chemical agents/drugs
- Infectious agents
- Immunologic reactions
- Genetic derangements
- Nutritional imbalances
Stresses or noxious stimuli first effect the cell at what level?
molecular or biochemical
what do molecular and biochemical changes in cells eventually lead to?
morphologic changes
Morphologic changes are associated with what effects in cell injury?
decreased ATP synthesis, loss of membrane integrity, defective protein synthesis,
cytoskeletal damage and DNA damage
Early cell injury morphological changes are (irreversible/reversible)
reversible
Persistent injury results in cell
death by necrosis or apoptosis
Reversible cell injury is recognized microscopically as
cellular swelling or fatty change
what cells typically show fatty change?
cells involved in and dependent upon fat metabolism
What are some ultrastructural changes of reversible cell injury
- Plasma membrane alterations, such as blebbing, blunting and loss if microvilli
- Mitochondrial changes including swelling
- Dilation of the ER along with detachment of the polysomes
- Nuclear alterations, with disaggregation of granular and fibrillar elements
The cellular response to stresses depends upon what three things?
the nature of the injury, its duration and severity.
Consequences of cell injury depend upon
the type of cell, its state and adaptability
, what are some mechanisms of cell injury?
- Depletion of ATP
- Mitochondrial damage
- Influx of calcium and loss of homeostasis
- Accumulation of oxygen
-derived free radicals
- Defects in membrane permeability
- Damage to DNA and proteins
Depletion of ATP occurs secondary to
- Reduced oxygen or nutrient supply
- Mitochondrial damage
- Toxins
why will mitochondrial damage lead to necrosis or apoptosis?
by depleting ATP or the release of apoptotic activating proteins
Influx of calcium activates what enzymes?
enzymes with the potential for membrane or nuclear damage
Free radicals (superoxide, hydrogen peroxide and hydroxyl radicals)
have a single unpaired electron
free radical damage occurs
secondary to lipid peroxidation in membranes, oxidative modifications of proteins or
DNA damage
Antioxidants
capable of inactivating free radicals and preventing cellular injury
Defects in membrane permeability lead to
membrane damage which is common to most forms of cell injury
what are the most common types of cell injury?
hypoxia & ischemia
Hypoxia
Reduced oxygen. Energy production able to continue by anaerobic means
Ischemia
Reduced blood flow
what provides an indication of cell death clinically?
the leakage of intracellular enzymes and other proteins into the blood
what are the effects of cellular ischemia?
- Loss of oxidative phosphorylation and decreased ATP
- Cell and mitochondrial swelling
- Surface "blebs"
- ER dilation
- Decreased protein synthesis
ischemia is (irreversible/reversible)
irreversible
hypoxia is (irreversible/reversible)
reversible
what are the Cellular changes of necrosis?
- Cell Swelling
- Cytoplasm becomes glassy, homogenous and pink and may have vacuoles
